Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing/filters: Add comment for match callbacks
  tracing/filters: Fix MATCH_FULL filter matching for PTR_STRING
  tracing/filters: Fix MATCH_MIDDLE_ONLY filter matching
  lib: Introduce strnstr()
  tracing/filters: Fix MATCH_END_ONLY filter matching
  tracing/filters: Fix MATCH_FRONT_ONLY filter matching
  ftrace: Fix MATCH_END_ONLY function filter
  tracing/x86: Derive arch from bits argument in recordmcount.pl
  ring-buffer: Add rb_list_head() wrapper around new reader page next field
  ring-buffer: Wrap a list.next reference with rb_list_head()

1 files changed, 20 insertions, 9 deletions

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 50504cb228de..e42af9aad69f 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -211,8 +211,9 @@ static int filter_pred_pchar(struct filter_pred *pred, void *event,
 {
 	char **addr = (char **)(event + pred->offset);
 	int cmp, match;
+	int len = strlen(*addr) + 1;	/* including tailing '\0' */
 
-	cmp = pred->regex.match(*addr, &pred->regex, pred->regex.field_len);
+	cmp = pred->regex.match(*addr, &pred->regex, len);
 
 	match = cmp ^ pred->not;
 
@@ -251,7 +252,18 @@ static int filter_pred_none(struct filter_pred *pred, void *event,
 	return 0;
 }
 
-/* Basic regex callbacks */
+/*
+ * regex_match_foo - Basic regex callbacks
+ *
+ * @str: the string to be searched
+ * @r:   the regex structure containing the pattern string
+ * @len: the length of the string to be searched (including '\0')
+ *
+ * Note:
+ * - @str might not be NULL-terminated if it's of type DYN_STRING
+ *   or STATIC_STRING
+ */
+
 static int regex_match_full(char *str, struct regex *r, int len)
 {
 	if (strncmp(str, r->pattern, len) == 0)
@@ -261,23 +273,24 @@ static int regex_match_full(char *str, struct regex *r, int len)
 
 static int regex_match_front(char *str, struct regex *r, int len)
 {
-	if (strncmp(str, r->pattern, len) == 0)
+	if (strncmp(str, r->pattern, r->len) == 0)
 		return 1;
 	return 0;
 }
 
 static int regex_match_middle(char *str, struct regex *r, int len)
 {
-	if (strstr(str, r->pattern))
+	if (strnstr(str, r->pattern, len))
 		return 1;
 	return 0;
 }
 
 static int regex_match_end(char *str, struct regex *r, int len)
 {
-	char *ptr = strstr(str, r->pattern);
+	int strlen = len - 1;
 
-	if (ptr && (ptr[r->len] == 0))
+	if (strlen >= r->len &&
+	    memcmp(str + strlen - r->len, r->pattern, r->len) == 0)
 		return 1;
 	return 0;
 }
@@ -781,10 +794,8 @@ static int filter_add_pred(struct filter_parse_state *ps,
 			pred->regex.field_len = field->size;
 		} else if (field->filter_type == FILTER_DYN_STRING)
 			fn = filter_pred_strloc;
-		else {
+		else
 			fn = filter_pred_pchar;
-			pred->regex.field_len = strlen(pred->regex.pattern);
-		}
 	} else {
 		if (field->is_signed)
 			ret = strict_strtoll(pred->regex.pattern, 0, &val);